I feel like one of the big reasons package managers aren't great with C is because of the way namespaces work.

It's not easy to have a medium-large codebase and just freely add a dependency because maybe this library causes variable or function name clashes. Even worse would be a macro that screws with your code.

There isn't even a simple solution like preprocessing everything in the downloaded library and adding a known prefix to every namespace encroaching identifier I think.